function [u]=Forward(u0,a,f)
    n=20;
    a_max = 1/pi^2;
    tao = 1/n^2;
    tao = tao*a_max/4;

    mu = tao*n^2*a_max;
    t_max =1;
    s = t_max/tao;
    u = zeros(n+1,floor(s));
    for i =1:n+1
        u(i,1)=u0((i-1)/n);
    end
    
    for t = 2: floor(s)
        for i=2:n
            u(i,t)=u(i,t-1)+mu*(u(i-1,t-1)-2*u(i,t-1)+u(i+1,t-1));
        end        
    end
end